Multi-level apparatus for folding large flexible webs

ABSTRACT

A multi-level apparatus for receiving a large flexible web, such as a large plastic bag, and folding it into multiple pre-selected segments in various configurations as may be desired. A plurality of conveyor decks are arranged in a stacked, spaced relationship relative to one another for sequentially receiving the flexible web which is to be folded. An adjustable actuator stop is associated with each conveyor deck for limiting the distance the leading portion of the web can advance along the deck, and conveyor means associated with each conveyor deck propels the flexible web therealong and into contact with the adjustable actuator stop. Counter-rotating elements positioned adjacent the front end of each conveyor deck in substantially longitudinal alignment with the top of the conveyor deck define a receiving slot to receive a pre-selected transverse segment of the flexible web along which it is desired to fold the web. Fold-starting means are included for urging the pre-selected transverse segment into the receiving slot. The adjustable actuator stop is operatively associated with the fold-starting means for actuation thereof, whereby upon engagement of the leading portion with the adjustable actuator stop, the transverse segment is urged into the receiving slot for initiating folding. A conveyor belt snakes between the counter-rotating elements and is arranged for contact therewith to convey the newly folding web therealong, the conveyor belt acting conjointly with the counterrotating elements to introduce a fold along a different preselected transverse segment of the flexible web at each receiving slot, whereby the flexible web may be folded into a plurality of segments of various sizes and configurations, as desired.

United States Patent 1 DAngelo 3,751,029 Aug. 7, 1973 PrimaryExaminer-Robert W. Michell Assistant Examiner-A. Heinz AttorneyBryan,Parmelee, Johnson & Bollinger [57] ABSTRACT A multi-level apparatus forreceiving a large flexible web, such as a large plastic bag, and foldingit into multiple pre-selected segments in various configurations asanother for sequentially receiving the flexible web which is to befolded. An adjustable actuator stop is associated with each conveyordeck for limiting the distance the leading portion of the web canadvance along the deck, and conveyor means associated with each conveyordeck propels the flexible web therealong and into contact with theadjustable actuator stop, Counterrotating elements positioned adjacentthe front end of each conveyor deck in substantially longitudinalalignment with the top of the conveyor deck define a receiving slot toreceive a pre-selected transverse segment of the flexible web alongwhich it is desired to fold the web. Fold-starting means are includedfor urging the pre-selected transverse segment into the receiving slot.The adjustable actuator stop is operatively associated with thefold-starting means for actuation thereof, whereby upon engagement ofthe leading portion with the adjustable actuator stop, the transversesegment is urged into the receiving slot for initiating folding. Aconveyor belt snakes between the counter-rotating elements and isarranged for contact therewith to convey the newly folding webtherealong, the conveyor belt acting conjointly with the counterrotatingelements to introduce a fold along a different preselected transversesegment of the flexible web at each receiving slot, whereby the flexibleweb may be folded into a plurality of segments of various sizes andconfigurations, as demay be desired. A plurality of conveyor decks arearsired ranged in a stacked, spaced relationship relative to one 2Claims, 10 Drawing Figures 1 l i M K 24 l m 12 1a 46 n L- l J5 41 1x .7650 ii i at f. "a l t I 1 I l a; I A

DESCRIPTION The invention relates to an app a ratus for folding largeflexible webs, for example, large plastic bags such as lawn cuttings andleaf bags, trash bags, disposable garbage-bags. The apparatus enablesthese items to be folded in various sizes and pre-selected patterns forease in handling and storage.

Prior art devices presently being employed for folding large flexiblewebs, especially large plastic bags are complex and subject to jammingand generally require elaborate adaptation when being used withconventional web making machines, i.e. bag making machines. That is, thecomplex prior folding devices have generally required mechanical andelectrical interconnections with the bag producing machine itself.Additionally, the prior devices have been limited in use that theygenerally require additional attachments and elaborate set-up proceduresto provide different fold configurations. Further, prior machines havefrequencly jammed during operation, and it is difficult and timeconsuming to clear the jam in such machines.

It is among the advantages of the apparatus embodying the presentinvention that it will readily accommodate different sizes of flexiblewebs and will produce folded webs of various sizes and configurationsand in which the folding pattern can be conveniently and easilypre-selected and changed, as may be desired by the operator.

It is a further advantage of the present apparatus that it may bereadily used with any conventional web or bag-making machine with aminimum of preparation and set-up time.

It is another advantage of the present invention in that there are norequired mechanical or electrical interconnections with the flexible webor bag producing machine. In other words, a machine embodying thepresent invention is universal in application.

It is a further advantage of the present invention in that the machineembodying this invention is essentially self-clearing.

It is a further advantage that the present apparatus is simple inconstruction and operation with few moving parts including a singlecontinuous conveyor belt.

It is a still further advantage that the flexible plastic web beingfolded is brought into contactwith metallic surfaces so that anytendencey toward static build-up on the plastic web is averted.

The invention provides a multi-level apparatus for receiving a largeflexible web and folding it into multiple pre-selected segments invarious configurations as may be desired by the operator. A plurality ofconveyor decks are arranged in a stacked, spaced relationship relativeto one another for sequentially receiving the flexible web which is tobe folded. An adjustable actuator stop is associated with each conveyordeck for limiting the distance the leading portion of the web canadvance along the deck, and conveyor means associated with each conveyordeck propels the flexible web therealong and into contact with theadjustable actuator stop. Counter-rotating elements positioned adjacentthe front end of each conveyor deck in substantially longitudinalalignment with the top of the conveyor deck define a receiving slot toreceive a preselected transverse segment of the flexible web along whichit is desired to fold the web. Fold-starting means are included forurging the desired pre-selected transverse segment into the receivingslot. The adjustable actuator stop is operatively associated with thefoldstarting means for actuation thereof, whereby upon engagement of theleading portion with the adjustable actuator stop, the desiredtransverse segment is urged into the receiving slot for initiatingfolding.

A continuous conveyor belt snakes between the counter-rotating elementsand is arranged for contact therewith to convey the newly folding webtherealong, the conveyor belt acting conjointly with the counterrotatingelements to introduce a fold along a different pre-selected transversesegment of the flexible web at each receiving slot, whereby the flexibleweb may be folded into a plurality of segments of various sizes andconfigurations or various patterns, as may be desired by the operator.

Other objects, aspects and advantages of the present invention will bemore fully understood from a consideration of the following detaileddescription in conjunction with the accompanying drawings, as follows:

FIG. 1 is a side elevational view, in partial section, showing a machineincluding the multi-level conveyor deck apparatus for folding largeflexible webs, for example, large plastic bags such as law-cuttings andleaf bags, trash bags, disposable garbage bags, and the like;

- FIG. 2 is a partial plan view of the multi-level deck apparatus shownin FIG. 1, with parts broken away;

FIG. 3 is an enlarged view of the counter-rotating elements shown inFIG. 1;

FIG. 4 is a side view of a large flexible web havng a single foldintroduced therein by apparatus embodying the present invention;

FIGS. 5 through 7 are side views of large flexible webs, such as largeplastic bags, having double folds introduced therein by the apparatusand showing the various fold configurations which may be achieved byadjusting the adjustable actuator stops along the respective conveyordecks; and

FIGS. 8 through 10 are side views of large flexible webs, such as largeplastic bags, having triple folds introduced therein by the apparatusand showing the various fold configurations which may be achieved byadjusting the adjustable actuator stops along the respective conveyordecks.

Referring to FIG. I, there is shown a web folding machine 10 which iswell suited for folding large plastic bags. This machine 10 includesmulti-level conveyor deck apparatus and is advantageous for use with aconventional web or bag making machine (not shown). The flexible web, asshown, is a large plastic bag 12 which has been fed into the machine 10from a conventional bag making machine at the left in FIG. 1 (not shown)and has been received at the receiving station, generally indicated at14. A plurality of spaced parallel continuous conveyor belts 16, 16A,16B, 16C, 16D and 16E (FIG. 2) are snaked between the receiving station14 and an exit station, generally indicated at 18 (FIG. 1). The speed ofthe composite conveyor belt 16-16E is adjusted to match the web outputspeed of the conventional bag making machine, through a variable speeddrive 20. c

The large plastic bag 12 is conveyed along by the composite conveyorbelt l6-I6E toward the first level or work station 21, and it is placedin compressive contact with a first comb tray or plurality of stripperblades 24 and rotating idler wheels 26 as it is conveyed to thecounter-rotating means 22. This counter-rotating means 22 includes afirst unitary metal roller 28 of the same diameter as a plurality ofindividual rollers 30 having a face width of 1% inches and having 74inch spacers positioned between them, as seen in FIG. 2. Theseindividual rollers 30 are all mounted on the same shaft 31 (FIGS. 1 and3) and, in effect, they cooperate to provide a segmented second rollwhich is in the counter-rotating opposition to the first roll 28.

This first set of rollers 28 and 30 are spaced relative to one anotherto form a first receiving slot 32. The continuous conveyor belt 16 issnaked diagonally down through the receiving slot 32, passing over thefirst roller 28 and passing beneath the second roller 30, andmaintaining tangential contact with both rollers 28 and 30.

Positioned adjacent the counter-rotating means 22 is a first metal,electrically conductive, conveyor deck 34 with its top surface 36substantially tangentially aligned as shown in FIGS. 1 and 3, with butslightly lower than the level of the top portion 38 of the roller 30.The airfloatation conveyor deck 34 is pivotally mounted at 42 to theframe 40 of the machine 10, so as to be capable of swinging about pivotconnection 42 for 90 movement from a substantially horizontal to asubstantially vertical position, as indicated at 34' by a dash anddotted outline in FIG. 1.

The counter-rotating roller means 22 is positioned in a slightlyelevated relationship relative to the front end 44 of the conveyor deck34; further, the first roller 28 is slightly'elevated relative to thesecond roller 30, e.g. the roller 28 being V4 inch higher. Thiselevation aids in initially conveying the leading end 46 of the largeplastic bag 12 across the receiving slot 32 (formed between the firstroller 28 and second roller 30) and onto the top surface 36 of theair-floatation conveyor deck 34.

Means 48 for imparting supporting air impulses to the large plastic bag12 as it moves and spans across the receiving slot 32 are positioned atthe front end 44 of the conveyor deck 34. The impulse imparting means48, shown as air jets, support the plastic bag 12 and prevent theleading edge 46 thereof from following the conveyor belt 16 down intothe receiving slot 32. These air jets direct streams of air, between thesegmented rollers 30, and the streams of air pass beneath the shaft 31and then the streams are deflected by the snaked belt 16, so that theair flow curves upward through the receiving slot 32. The upward flow ofair through the space 32 supports the bag 12.

Conveyor means, shown as alternate air slits 50 in the conveyor deck 34,provide air streams which angle upwardly to strike the lower surface ofthe large plastic bag 12 above the conveyor deck 34 providing ahorizintal force component to the large plastic bag 12 to thereby conveythe large plastic bag 12 by air floatation along the conveyor deck 34.

Positioned on the conveyor deck 34 is a ramp positioning means, shown asa metal strip 52 for lifting the leading end of the bag 12 into positionto strike against the adjustable actuator stop means, shown as amicroswitch 54. This microswitch is capable of being adjustablypositioned along the strip 52. The large plastic bag 12 is moved alongthe conveyor deck 34 and along the metal strip 52 until the leading edge46 strikes the adjustable actuator stop means 54.

As mentioned above, this adjustable actuator stop means 54 may beadjustably positioned anywhere along the metal strip 52. Its position isdetermined by considering the total length of the large plastic bag 12and the desired relative location of the transverse segment of the bagas indicated at 56, at which it is desired to introduce a fold. When theactuator stop 54 is engaged by the leading end of the bag, the forwardmovement of the bag is momentarily stopped, and the switch 54 causes thetransverse bag segment 56 to be urged down into the slot 32 by foldinitiating means 58, shown as an air tube. A momentary blast of air downthrough a plurality of ports in the bottom of the horizontal air tube 58drives the bag portion 56 down into the nip region between the belt 16and the roller 30. The bag is thereby folded at 56, and is pulled downbeneath the roller 30.

The folded bag segment 56, urged into the receiving slot 32, is nippedbetween the conveyor belt 16 extending diagonally 'therethrough and thesecond roller 30 acting conjointly therewith to compress the plastic bag12 along the transverse segment 56 introducing a fold therealong. Theremaining portions of the large plastic bag 12, on both sides of thefolded transverse segment 56, are pulled down beneath the roller 30 tofollow the transverse segment 56 which has now become the new leadingedge. I

It is noted that there is a short approximately horizontal belt section63 after the belt 16 has curved down around the segmented roller 30 andbefore the belt 16 begins snaking down diagonally between the second setof counter-rotating rollers 68 and 70.

The singly folded bag 60 (FIG. 1) passes onto the second level or workstation 61. This singly folded bag 60 is placed in stripping guidingcontact with the second comb tray or plurality of stripper blades 62, asit passes above the second counter-rotating means 64 and onto the secondair-floatation conveyor deck 66. The plurality of stripper blades 62prevent the singly folded bag 60 from following up around the path ofrotation of the second roller 30, which might otherwise cause the bag tojam up into the space between the roller 30 and the end 44 of the firstdeck 34.

The rollers 68 and of the second counter-rotating means 64 are similarin construction and arrangement with the first and second rollers 28 and30 respectively, of the first counter-rotating means 22. The secondcounter-rotating means 64 is also positioned relative to the secondconveyor deck 66 in the same relationship as the first counter-rotatingmeans 22 relative to the first conveyor deck 34. Further, the rollers 68and 70 form a second receiving slot 72 with the conveyor belt 16 snakingdiagonally down through the slot 72 in tangential contact with the topof roller 68 and the bottom of roller 70. The roller 68 is of unitaryconstruction, and the roller 70 is of segmented construction, just likeroller 30.

A second fold-initiation air tube 74 is associated with the secondreceiving slot 72. Also, second air jets 76 are positioned in the frontend 78 of the second conveyor deck 66 for providing a flow of airbeneath the roller shaft 71 upward through the slot 72 for temporarilysupporting the bag as it spans across the slot 72. The second conveyordeck 66 also has a metal ramp leading end positioning strip 80 withadjustable actuator stop means 82positioned thereon and has alternateair slits 83 arranged therein. This second level 61 performs the samefunctions as the first level 21 and is capable of introducing a secondfold in the plastic bag 12 along a desired transverse region 84.

The transverse segment 84, folded in the second receiving slot 72,thereby becomes the new leading edge 84 as the double-folded bag 85 isconveyed to the third level or work station 86. The same functions takeplace at the third level 86, which includes third counterrotating means88 and a third air-floatation conveyor deck 90, as have occurred at thetwo previous levels 2i and 61. Thus, the third level introduces a thirdtransverse fold into the plastic bag 12.

Support tube 92 does not produce an air stream since the conveyor belt16 conveys the tri-folded bag 12 from the third receiving slot 93directly to exit station 18. There are stripper elements 62 supported bythe foldinitiating tube 100 and also by the support 92. There are airjets 76 at the front end of the third deck 99 for supporting the bagspanned across the slot 93 between rollers 101 and 102. The exit station18 is effectively down at a fourth level in the multi-level conveyorapparatus ll. 1

The three conveyor decks 34, 66 and 90 are arranged in a horizontalstacked spaced relationship relative to one another. The conveyor decks66 and 90 are also pivotally mounted to the frame 40 of the apparatus1119, about respective pivot connections 94 and 96, in like manner aspreviously described with respect to the first conveyor deck 34. Such amulti-level stacked spaced arrangement with pivotally mounted conveyordecks facilitates easy access to lower levels should a plastic bagbecome jammed in the multi-level conveyor apparatus 11. These threeconveyor decks may be readily swung 90 up to vertical, out-of-the-waypositions 34, 60' and 90 (see FIG. 1) for clearing a jam or foradjusting the position of the respective adjustable actuator stop means82 and 84 along the positioning strips 80 on lower levels.

Additionally, as shown in FIG. 1, the conveyor decks 34, 66 and 90arehollow chambers with air supply conduits through thepivotally hingedjoints 42, 94 and 96, respectively. These pivot connection conduits d9,9d and 96 communicate with a pressurized air source, for example, a ductsystem 99 supplied by a motor driven blower 59'. Alternatively, theframe 49 may be arranged to define a pressurized air supply plenumchamber to which the connections 49, 94 and 96 are joined. Then theblower 59 supplies the plenum chamber.

Referring specifically to FIG. 3 of the drawings, there is levelby-passing means 98 for preventing transmission of the leading edge ofthe plastic bag 12 to the individual conveyor decks. This by-pass means98 may be employed to introduce a lesser number of folds (than three) inthe plastic bag 12. The by-pass means, shown in dotted outline in FIG.3, is a removable baffle 99 conveniently hung upon and extendingdownwardly from the second fold-initiating air tube 7d.

The removable baffle 98 may also be readily hung from the first air tube58 or from the third air tube 109. Further, if desired, two baffles 98may be employed to produce only a single fold in the plastic bag 12.Access to the air tubes 74 and 100, associated with the second and thirdlevels 61 and 86, respectively, for mounting the by-pass baffle orbaffles 98, may be readily ob tained by swinging the upper conveyordecks upward to their vertical positions as shown in FIG. l.

The by-pass baffle 98 will direct the leading end of the plastic bagdirectly into the respective receiving slot associated therewtih,preventing the leading end from entering the particular deck level andconsequently preventing a fold from being introduced in the plastic bag1132 at that respective level.

In many plastic web handling machines there is a problem due to build upof static electricity on the web. Such static electricity causes the webto cling and become difficult to handle. Elaborate high voltagedischarge devides are often required to be employed in the prior art.

The plastic bag 12 in contact with the conveyor belt l6, normally has atendency to become charged up with static electricity. The metalconveyor decks 34, 66 and 9t) and also the second segmented metalrollers 30, 79 and 102 of the counter-rotating means 22, 64 and 88,respectively, with which the plastic bag 12 comes in contact, serve asconductors for the discharge of any static electricity. Thus, the buildup of static electricity is advantageously avoided without; requiringany elaborate discharge devices.

It should be appreciated that "this multi-level conveyor apparatus Itfor folding large plastic bags 12 can adjust to any bag length over alarge range and to fold a bag into any desired length segments byadjusting the positions of the adjustable actuator stop means 54, 82 and84. Additionally, the number of folds can be increased by increasing thenumber of levels. Further, the number of folds can be readily reduced byemploying one or more lay-passing baffle means 98.

Particularly, with reference to FIGS. 4 through '10, the versatility ofthe apparatus 10 in providing different fold configurations orarrangements of folds is apparent. If it is desired to introduce onlyone fold, as shown in FIG. 4, baffles 98 may be utilized to bypass twoof the three conveyor decks. As shown in FIGS. 5 through '7', if it isdesired to produce two folds, a single by-pass baffle 98 is used todirect the leading edge emerging from the preceding set of rollersdirectly to the next receiving slot without introducing a fold in theplastic bag.

Further, the differnet two-fold configurations shown in FIGS. 9 through'7 may be produced by varying the respective positions of the adjustableactuator stop means along the two conveyor decks which are beingutilized.

FIGS. 9 through lit) show the different three-fold configurations thatmay be obtained when utilizing all three conveyor decks and varying therespective positions of the adjustable actuator stop means 54, 82 and 94along the three conveyor decks.

The air slits of outlets S9, 83 and 85 in the respective conveyor decksare alternately arranged (or staggered) in successive lines (or rows) asseen in FIG. 2. These outlets are formed by depressing the downstreamlips of the slits to create an upwardly inclined and downstream directednozzle action.

ments, the number of folds capable of being made corresponding to thenumber of levels in the apparatus, said apparatus comprising:

a plurality of conveyor decks arranged in a vertically spaced stackedrelationship relative to one another defining a number of levels equalto the number of said decks;

each of said decks having a front end and being adapted for receiving aleading portion of the individual flexible webs to be folded;

adjustable actuator stop means associated with each of said conveyordecks and being spaced from the front end of the respective decks forlimiting the distance the leading portion of the individual webs canadvance from the front end along each of said conveyor decks;

means for conveying the individual webs along each of said conveyordecks so that their leading portions will contact said adjustableactuator stop means associated therewith;

counter-rotating means positioned adjacent the front end of each of saidconveyor decks and in substantially tangential alingment therewith, eachof said counter-rotating means including counter-rotating rolls and areceiving slot for receiving a transverse segment of the web along whichit is desired to introduce a fold; I

means associated with each of said receiving slots for urging thedesired transverse segment of the individual webs into said respectivereceiving slots, said urging means being actuated when the leading webportions engage said adjustable actuator stop means associated with theadjacent conveyor deck, whereby the desired transverse segment of theweb said plurality of stacked conveyor decks being pivotally connectedto said apparatus for movement to an out of the way position to allowready access to said adjustable actuator stop means positioned on therespective lower conveyor decks for adjusting the position of saidadjustable actuator stop means and to allow ready access to therespective adjacent counter-rotating means should a flexible web bejammed therein,

whereby the individual flexible webs are folded into a multiplicity ofsegments for ease in handling and storage.

2. A multi-level apparatus for folding large flexible webs as claimed inclaim 1, in which:

each of said conveyor decks is hollow forming an air chamber therein,

a pressurized air .source communicates with the chamber in each of saiddecks, and each of said conveyor decks having a plurality of openingstherein directed upwardly at an angle away from the front end of thedeck for conveying the plastic web by air floatation away from the frontend toward the actuator stop means associated therewith.

1. A multi-level apparatus for folding large flexible webs, for example,such as large plastic bags, adapted to fold the individual flexible websinto multiple segments, the number of folds capable of being madecorresponding to the number of levels in the apparatus, said apparatuscomprising: a plurality of conveyor decks arranged in a verticallyspaced stacked relationship relative to one another defining a number oflevels equal to the number of said decks; each of said decks having afront end and being adapted for receiving a leading portion of theindividual flexible webs to be folded; adjustable actuator stop meansassociated with each of said conveyor decks and being spaced from thefront end of the respective decks for limiting the distance the leadingportion of the individual webs can advance from the front end along eachof said conveyor decks; means for conveying the individual webs alongeach of said conveyor decks so that their leading portions will contactsaid adjustable actuator stop means associated therewith;counter-rotating means positioned adjacent the front end of each of saidconveyor decks and in substantially tangential alingment therewith, eachof said counter-rotating means including counter-rotating rolls and areceiving slot for receiving a transverse segment of the web along whichit is desired to introduce a fold; means associated with each of saidreceiving slots for urging the desired transverse segment of theindividual webs into said respective receiving slots, said urging meansbeing actuated when the leading web portions engage said adjustableactuator stop means associated with the adjacent conveyor deck, wherebythe desired transverse segment of the web along which a fold is to beintroduced is urged into said receiving slot; a conveyor belt extendingbetween said counter-rotating means and in contact therewith to conveythe flexible web therealong and acting conjointly with saidcounter-rotating means to fold the transverse segment of the flexibleweb which is urged into each of said receiving slots at the variouslevels; and said plurality of stacked conveyor decks being pivotallyconnected to said apparatus for movement to an out of the way positionto allow ready access to said adjustable actuator stop means positionedon the respective lower conveyor decks for adjusting the position ofsaid adjustable actuator stop means and to allow ready access to therespective adjacent counterrotating means should a flexible web bejammed therein, whereby the individual flexible webs are folded into amultiplicity of segments for ease in handling and storage.
 2. Amulti-level apparatus for folding large flexible webs as claimed inclaim 1, in which: each of said conveyor decks is hollow forming an airchamber therein, a pressurized air source communicates with the chamberin each of said decks, and each of said conveyor decks having aplurality of openings therein directed upwardly at an angle away fromthe front end of the deck for conveying the plastic web by airfloatation away from the front end toward the actuator stop meansassociated therewith.